1. Field of the Invention
This invention relates generally to synchronization of objects and relates more particularly to a system and method for synchronization of version annotated objects.
2. Description of the Background Art
Various types of data are stored in computers such as servers and desktop personal computers (PCs) that are not generally considered mobile devices. Some types of data, for example contact information, are commonly stored both in a non-mobile computer and a mobile device such as a personal digital assistant (PDA) or other handheld computer or device. It is often desirable and necessary to synchronize the data in a non-mobile computer and a mobile device. In general, data synchronization involves change identification, conflict detection, and conflict resolution. Various techniques exist for accomplishing these aspects of data synchronization, including (1) comparing the data object by object for changes and differences, (2) logging changes made at each device, exchanging logs, and applying changes from each device's log to the other device, and (3) comparing objects in each device against objects in a history file that reflects the data in each device at the completion of the last synchronization.
Data synchronization often occurs in a single-user context where the data is typically stored in only two devices, a mobile device such as a PDA and a non-mobile device such as a desktop PC. Synchronization of single-user data is typically straightforward since only two sets of data need to be synchronized. Synchronization of multiple-user data that resides in more than two databases presents more of a challenge. Multiple users of data increase the likelihood of conflicts between the different databases and complicate the resolution of such conflicts.